Control system

Abstract

The present invention provides a control system for controlling the ice volume fraction of a circulating ice-containing medium. The control system comprises a freezer apparatus for generating an ice-containing medium, a pump for circulating the ice-containing medium through a flow circuit comprising an outward line, a main line and a return line, and a bypass line connecting the outward line and return line to form a bypass circuit. In use, the time taken for circulating ice-containing medium to pass through the bypass circuit is less than the time taken for circulating ice-containing medium to pass through the flow circuit. The present invention also provides a method for controlling the ice volume fraction of a circulating ice-containing medium using such a control system.

1 . A control system for controlling the ice volume fraction of a circulating ice-containing medium, the control system comprising:
 a freezer apparatus for generating an ice-containing medium;   a pump for circulating the ice-containing medium through a flow circuit comprising an outward line, a main line and a return line; and   a bypass line connecting the outward line and return line to form a bypass circuit such that, in use, the time taken for circulating ice-containing medium to pass through the bypass circuit is less than the time taken for circulating ice-containing medium to pass through the flow circuit.   
   
   
       2 . A control system according to  claim 1  wherein the bypass line and the main line in the flow circuit are of comparable internal diameter and the length of the flow circuit main line is greater than the length of the bypass line. 
   
   
       3 . A control system according to  claim 1  wherein the volume of the bypass line is less than the volume of the flow circuit main line. 
   
   
       4 . A control system according to  claim 1  wherein the bypass line includes a restrictor. 
   
   
       5 . A control system according to  claim 1  wherein the bypass line connects to a point on the outward line in close proximity to the freezer apparatus. 
   
   
       6 . A control system according to  claim 1  wherein the system further comprises a source liquid inlet line in fluid communication with the return line. 
   
   
       7 . A control system according to  claim 1  wherein the system further comprises a controller for controlling the operation of the freezer apparatus, the controller being connected to one or more detection element(s) in the flow circuit and/or bypass circuit. 
   
   
       8 . A control system according to  claim 7  wherein the detection element(s) include one or more ice fraction sensors and/or one or more flow rate meters and/or one or more temperature sensors. 
   
   
       9 . A control system according to  claim 8  wherein the detection element(s) comprise(s) one or more ice fraction sensors located in the outward line and/or the return line and/or the bypass line. 
   
   
       10 . A control system according to  claim 9  comprising an ice fraction sensor in the 
   
   
       11 . A control system according to  claim 10  further comprising a delay buffer zone between the ice fraction sensor in the return line and the freezer apparatus. 
   
   
       12 . A control system according to  claim 10  wherein the bypass line connects to the return line at a position before the ice fraction sensor in the return line. 
   
   
       13 . A control system according to  claim 8  comprising an ice fraction sensor in the outward line and/or bypass line. 
   
   
       14 . A control system according to  claim 8  when dependent upon  claim 6  comprising a flow rate meter in the source liquid inlet line. 
   
   
       15 . A control system according to  claim 1  wherein the flow circuit is a cooling circuit. 
   
   
       16 . A beverage dispense system comprising a control system as defined in  claim 1 . 
   
   
       17 . A beverage dispense system according to  claim 16  comprising an ice-containing medium dispense valve for dispensing ice-containing medium. 
   
   
       18 . A method for controlling the ice volume fraction of a circulating ice-containing medium, the method comprising:
 generating an ice-containing medium using a freezer apparatus;   providing a flow circuit comprising an outward line, a main line and a return line;   providing a bypass line connecting the outward line and return line to form a bypass circuit; and   circulating the ice-containing medium around the flow circuit and the bypass circuit using a pump such that the time taken for circulating ice-containing medium to pass through the bypass circuit is less than the time taken for circulating ice containing medium to pass through the flow circuit.   
   
   
       19 . A method according to  claim 18  further comprising measuring data using one or more detection element(s) in the flow circuit and/or bypass circuit, the detection element(s) being connected to a controller. 
   
   
       20 . A method according to  claim 19  comprising measuring the ice volume fraction of the ice-containing medium using one or more ice fraction sensors, and/or measuring flow rate using one or more flow rate meters and/or measuring ice-containing medium temperature using one or more temperature sensors. 
   
   
       21 . A method according to  claim 20  comprising measuring the ice volume fraction of the ice-containing medium using one or more ice fraction sensors located in the outward line and/or the bypass line and/or the return line. 
   
   
       22 . A method according to  claim 21  comprising measuring the ice volume fraction of the ice-containing medium using an ice fraction sensor in the return line. 
   
   
       23 . A method according to  claim 22  comprising providing a flow delay between the ice fraction sensor in the return line and the freezer apparatus. 
   
   
       24 . A method according to  claim 20  comprising measuring the ice volume fraction of the ice-containing medium using an ice fraction sensor in the outward line and/or the bypass line. 
   
   
       25 . A method according to  claim 20  comprising measuring the flow rate of a source liquid in a source liquid inlet line, the source liquid line being connected to the return line. 
   
   
       26 . A method according to  claim 18  comprising generating an ice-containing medium comprising a free-flowing liquid suspending ice particles or generating an ice-containing medium having a slush consistency. 
   
   
       27 . A method according to  claim 18  comprising allowing heat exchange between the ice-containing medium in the main line of the flow circuit and a warmer medium requiring cooling. 
   
   
       28 . A method of cooling a beverage using an ice-containing medium having an ice volume fraction controlled by a method as defined in  claim 18  comprising allow heat exchange between the beverage and the ice-containing medium. 
   
   
       29 . A method of dispensing a beverage ice-containing medium having ice volume fraction controlled by a method as defined in  claim 18 , comprising dispensing the beverage ice-containing medium from a dispense valve at a dispensation site. 
   
   
       30 - 32 . (canceled)